Cher missed out on "a lot of money" after failing to secure a writing credit on 'Believe'.
The 77-year-old singer admitted one of her biggest regrets was being too "stupid" to ask for her contribution to the 1998 single - which was formally credited to Brian Higgins, Stuart McLennen, Paul Barry, Steven Torch, Matthew Gray, and Timothy Powell - to be officially recognised because the song went on to sell more than 11 million copies around the world.
Speaking on BBC Radio 2's 'Tracks Of My Years', she told host Vernon Kay: "You can’t even imagine — about 30 people wrote on it. And I was so stupid. I didn’t ask. I didn’t even get a writer’s credit.
“I wrote, ‘I’ve had time to think it through, and maybe I’m too good for you’.
“It sold 11million copies. I could have got a lot of money.”
Cher recalled how tense recording the song was and she even walked out of the studio when her vocals were criticised.
She laughed: “The verse was so bad. I couldn’t make it good.
“We — the songwriters and I — got into a big fight over it. I walked out after they said I had to sing it better.
“Then in the morning I said ‘[Use] a vocoder?’ and they said, ‘No, you’ve got to do it at the time [live]’.”
But the track was eventually altered and Cher loves how unrecognisable her voice is in parts of the song.
She said: “My favourite thing was that you didn’t know it was my voice at the beginning."
The veteran singer is currently promoting her first ever festive album, which is titled 'Christmas', but she insisted she just wanted to make people "feel happy", rather than place particular emphasis on the holiday season.
She said: “I don’t want people to think of me and Christmas as one with this album.
“What I wanted to do was make an album that would make people feel happy,
“I wanted it to be joyous. I just wanted to pick songs that even if it doesn’t go together, it makes you feel better.”
And she dismissed speculation she is trying to take the festive crown away from 'All I Want For Christmas is You' hitmaker Mariah Carey.
She said: “Mariah is a great vocalist.
“She can do amazing things with her voice. It’s unbelievable.
“'All I Want For Christmas' is on my playlist.
“When you hear what she can do with her voice . . . it’s such a thrill to hear someone who sings so well.”
Tagged in Cher Mariah Carey Vernon Kay